Yamaha YZF-R125 Owners Manual: Motorcycle care and storage

Troubleshooting charts

Starting problems or poor engine performance Starting problems or poor engine performance Engine overheating WARNING Do not remove the radiator cap when the engine and radiator are hot. S ...

Matte color caution

NOTICE Some models are equipped with matte colored finished parts. Be sure to consult a Yamaha dealer for advice on what products to use before cleaning the vehicle. Using a brush, harsh ch ...

Other materials:

Checking the starter clutch
1. Check: Starter clutch rollers "1" Starter clutch spring caps "2" Starter clutch springs "3" Damage/wear Replace the starter clutch assembly. 2. Check: Starter clutch idle gear Starter clutch gear Burrs/chips/roughness/wear Replace the defective part(s). 3. Check: ...

Checking the valve seats
The following procedure applies to all of the valves and valve seats. 1. Eliminate: Carbon deposits (from the valve face and valve seat) 2. Check: Valve seat Pitting/wear Replace the cylinder head. 3. Measure: Valve seat width C "a" Out of specification Replace the ...

Checking the crankshaft
1. Measure: Crankshaft runout Out of specification Replace the crankshaft, bearing or both. NOTE: Turn the crankshaft slowly. 2. Measure: Big end side clearance Out of specification Replace the crankshaft. 3. Measure: Crankshaft width Out of specification&nbs ...